Reserved request type of searched information distribution server

ABSTRACT

The reserved request type of searched information distribution server having a first function unit for issuing a search request to another server connected to the Internet via the Internet so as to collect desired data from a WWW server specified by the search request according to the schedule specified by the search request when receiving a request of data searching in a WWW server from a client terminal, and a second function unit for receiving searched data via a communication satellite.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a method and a system forsearching and collecting data from information providing servers, thatis, World Wide Web (WWW) servers through the Internet, more particularlyto a method and a system for searching data requested from a pluralityof client terminals collectively at fixed intervals of time (at fixedtimes) according to the reserved search requests from those clientterminals and distributing searched data to each of those clientterminals.

[0003] 2. Description of Related Art

[0004] Now that the use of the Internet has come into an explosiveincrease, it is possible to access World Wide Web (WWW) servers, whichare information providing servers connected to the Internet, from anyplace in the world. The Internet and the WWW are described in detail inthe following publications.

[0005] (1) Internet User's Guide; written by Ed Krol, translated by JunMurai, and published by Tomson Publishing Japan.

[0006] (2) The Whole Internet; written by Ed Krol and published byOreilly Associates, Inc. which is an original of the publication (1).

[0007] If an Internet user makes an attempt to obtain data from a WWWserver, for example, using a client terminal, which is a personalcomputer (PC) or a work station (WS) so as to collect data distributedthroughout the world, the user may have to wait for a long time untilhe/she obtains desired data after he/she issues a request depending onthe operation hour and the object WWW server. This problem may alsooccur in the following cases; when the accessed Internet route isinsufficient in capacity to cope with the access speed, when accesses toa specific WWW server are over-concentrated, and when the access is madevia a specific relay point (generally, it is also referred to as a hub).

SUMMARY OF THE INVENTION

[0008] Now that the Internet allows data to be searched from WWW serversdisposed distributively throughout the world, such the advantage of theInternet should be used more practically.

[0009] Using a communication satellite will be one of the effectivemethods for obtaining data from Internet WWW servers at high speeds.Such two-way communications, however, require an expensive transmittingfacility. Practically, therefore, such a communication satellite isusually used only for receiving data from WWW servers.

[0010] On the other hand, the user may search and collect data regularlyand search and collect non-emergency data from WWW servers connected tothe Internet at fixed intervals of time. In such non-real time datasearching, it would be convenient if it is possible that reserved searchrequests are registered beforehand so that WWW servers are accessed atfixed intervals of time, although such a function is not realized yet.

[0011] Under such the circumstances, it is an abject of the presentinvention to provide a method and a system that can reserve a searchitem beforehand from a client terminal and distribute data searched froman object Internet WWW server according to the reserved search item tothe client terminal collectively at fixed intervals of time whensearched information is to be obtained from an information providingserver connected to the Internet.

[0012] It is another object of the present invention to provide a methodand a system that can receive searched data collectively from an objectInternet WWW server at fixed intervals of time via a communicationsatellite and distribute received searched data to the request sourceclient terminal.

[0013] In order to achieve the above mentioned objects, the reservedrequest type of information search and distribution system of thepresent invention is provided with a searching server and a satellitecommunication server so that the system can process reserved searchrequests from client terminals.

[0014] Receiving a reserved search request from a client terminal, thesearching server searches specified data from each WWW server connectedto the Internet and saves searched data in a cache file provided in thesearching server. After this, the system transmits collected searcheddata to the client terminal sequentially.

[0015] According to the present invention, collected data is transmittedto the object client terminal, for example, at 12 a.m., at 8 a.m., atnoon, at 5 p.m. every day, or when the client terminal is connected tothe searching server.

[0016] Furthermore, the above mentioned searching server is providedwith a function for communicating with a network access center of theInternet so that the server can issue reserved search requests from aplurality of client terminals collectively to the network access center,and the network access center operates to search and collect data fromWWW servers connected to the Internet.

[0017] Such a network access center is convenient to search and collectdata from object WWW servers instead of a searching server when thoseWWW servers exist in a specific relay point or in a specific relay areain a different country in which the searching server does not exist, forexample, when the searching server exists in Japan and the object WWWservers and the network access center exist in the United States ofAmerica.

[0018] The data searched and collected by the network access center fromWWW servers is transmitted to a satellite communication server via acommunication satellite. The satellite communication server transfersthe received data to the searching server sequentially. The searchingserver saves data received from the satellite communication server in acache file sequentially. Then, in a fixed time, the searching serverreads the data from the cache file and transmits it to the object clientterminal.

[0019] According to the present invention, by using the satellitecommunication server as a communication unit for exclusively receivingthe searched data from the communication satellite, the data searchedfrom WWW servers existing in a specific relay area can be receivedcollectively at a high speed so as to reduce the required searching andcollecting time significantly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 is a functional block diagram of a reserved request type ofinformation search and distribution system of the present invention.

[0021]FIG. 2 is a format of a request data block to be communicatedbetween a searching server and a client terminal, as well as between asearching server and a satellite communication server.

[0022]FIG. 3 shows the correspondence between types of request codes andrequest contents in a request data block.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereunder, the reserved request type of information search anddistribution system of the present invention will be described in detailwith reference to a preferred embodiment shown in the accompanyingdrawings.

[0024] In FIG. 1, the reserved request type of information search anddistribution system of the present invention is provided with asearching server 1 and a satellite communication server 2. A cache file3 is connected to the searching server 1. Both the searching server 1and satellite communication server 2 are connected to each other via anetwork, for example, a local area network (LAN) 4. The servers 1 and 2are also connected to client terminals 6 a to 6 c via a LAN 5 and arouter 5 a.

[0025] Each of the client terminals 6 a to 6 c, etc. is provided with acommunication function. The client terminal may be a personal computer(PC) or a work station (WS). An operating system OS (not illustrated)provided with communication functions is running in both of thesearching server 1 and the satellite communication server 2.

[0026] In the searching server 1 for realizing both method and system ofthe present invention for searching and distributing reserved requesttype of information are running a request, search, and delivery unit 13,an Internet access processing unit (INTAC) 14, a cache file input/outputprocessing unit 15, a LAN communication unit 16, and a wake-upprocessing unit (WKUP) 17 for starting up the above mentioned Internetaccess processing unit 14 at fixed intervals of time.

[0027]FIG. 2 shows an example of the format of a request data block(REQT) 20 transmitted from client terminals 6 a to 6 c, etc. to thesearching server 1.

[0028] The request data block 20 comprises a request code 21, adestination IP address 22, a source IP address 23, a sub-code 24, andthe URL (Universal Request Locator) of each of object WWW servers S1 toSn. For details of the URL, refer to the above mentioned publications.

[0029]FIG. 3 shows the correspondence between the types of request codes21 and request contents in the request data block 20 shown in FIG. 2.

[0030] Receiving this request data block 20, the reserve, search, anddelivery unit 13 checks the request code 21 in the request data blockthereby to execute a processing according to the request content shownin FIG. 3.

[0031] (1) Reserved search request (RQ=1)

[0032] This request is issued to register the request content of theclient terminal 6 a in a user table (USER) 27. When registering therequest content, the S-IP field 23 of the request data block 20 forsetting a source IP address is corresponded to the IP 27 a in the usertable 27 and the URL fields 25 a to 25 n to the RURL 28 respectively.

[0033] In the sub-code field 24, a searching mode, for example,searching at a fixed time or searching at fixed intervals of time isspecified. This searching mode information is also saved in the usertable 27. A source IP address set in the S-IP field 23 is the address ofthe client terminal 6 a. This address value is decided uniquely as aTCP/IP (Transmission Control Protocol/Internet Protocol) address valueon an object LAN. The TCP/IP is also described in detail in the abovementioned publications. The TCP/IP address value of the searching server1 is set in the S-IP field 23 of the request data block 20.

[0034] (2) Direct search request (RQ=2)

[0035] In order to obtain the URL information specified by URL1 to URLn,the reserve, search, and delivery unit 13 issues this direct searchrequest immediately to the WWW servers 8 a to 8 d connected to theInternet 7 respectively. At this time, if caching is specified in thesub-code field 24, the unit 13 checks the searched data management table(SIND) 30.

[0036] If there is a URL 32 which is equal to the specified URL1:25 a,it means that the URL 32 is already saved in the cache file 3. Thus, theunit 13 reads the data 34 corresponding to the URL1 in the cache file 3and transmits the data 34 to the client terminal 6 a via the LAN 4.

[0037] If no caching is specified in the sub-code field 24 or if thespecified URL is not registered in the searched data management table30, then the unit 13 starts up the Internet access processing unit 14 sothat this Internet access processing unit 14 issues a request to the WWWservers 8 a to 8 d so as to search and collect the specified URL fromthose WWW servers connected to the Internet 7. For example, if a WWWserver having the data of the requested URL 25 a is the WWW server 8 a,the requested data is returned from this WWW server 8 a via the Internet7.

[0038] The reserve, search, and delivery unit 13 provided in thesearching server 1 registers the data received time TM 31 and the URL 32in the searched data management table 30, saves the received data in thecache file 3, and transmits the searched data to the request sourceclient terminal 6 a via the LAN 4, the router 5 a, and the LAN 5. Thereason why caching is made such way in the searching server 1 is to makeit faster to process the next request and the same URL search requestissued from other client terminals 6 b and 6 c.

[0039] (3) Status check request (RQ=3)

[0040] This request is issued from the client terminal 6 a, etc. toinquire of the searching server 1 about the searching status. If thisrequest is issued, the reserve, search, and delivery unit 13 checks bothuser management table 27 and searched data management table 30 therebyto check if the latest URL data requested by the client terminal 6 a isalready received or not.

[0041] If the URL data is already received, the unit 13 notifies theclient terminal 6 a of the result by transmitting the request data block20 to the client terminal 6 a. In the request data block 20, the addressof the client terminal and the address of the searching server address 1are set in the D-IP field 22 and in the S-IP field 23 respectively, and“latest data present” is marked in the sub-code field 24.

[0042] If the latest URL data is not received yet, “latest data notpresent” is marked in the sub-code field 24 before the request datablock 20 is transmitted to the client terminal 6 a.

[0043] (4) URL data receiving request (RQ=4)

[0044] Receiving this request from the client terminal 6 a, the reserve,search, and delivery unit 13 obtains URL data from the RURL 28 of the IP27 a corresponding to the address of the client terminal registered inthe user management table 27, then transmits the data 34 of the URL 33,which matches with the URL 32 in the searched data management table 30,from the cashe file 3 to the client terminal 6 a.

[0045] (5) Data reload request (RQ=5)

[0046] This request is issued from the satellite communication server 2.Receiving this request from the satellite communication server 2, thereserve, search, and delivery unit 13 prepares for receiving the latestURL data 40 a and the data received time (TM) 42 from the satellitecommunication server 2. Hereafter, the unit 13 receives the datareceived time 42, the URL 43, and the data 40 a and 40 b sequentiallyfrom the satellite communication server 2 thereby to update the searcheddata management table 30, the table 33 and the data 34 in the cache file3 respectively.

[0047] Next, the operation of the reserved searching function, which isone of the features of the present invention, will be described.

[0048] The searching server 1 controls the reserved searching function.The wake-up processing unit (WKUP) 17 provided in the searching server 1starts up the Internet access processing unit 14 at every fixed time,for example, at 12 a.m., at 8 a.m., at noon, or at 5 p.m. every day. Thewake-up processing unit (WKUP) 17 may also start up the Internet accessprocessing unit 14 at fixed intervals of time.

[0049] The Internet access processing unit 14, when started up from thewake-up processing unit (WKUP) 17, fetches RURL 28 registered in theuser management table 27 and instructs the network access center 9 tosearch URL data collectively from the WWW servers 8 a to 8 n.

[0050] The network access center 9 existing at a specific relay point orin a specific relay area then searches the data corresponding to thespecified URL and saves the searched data in a file 9 a temporarily.After this, the center 9 transmits the searched data to the satellitecommunication server 2 via the transmission antenna 10, then via thecommunication satellite 11 and the reception antenna 12.

[0051] The data receiving unit 39 provided in the satellitecommunication server 2 passes received data to the URL data managementunit 38. The URL data management unit 38 saves URL data 40 a and 40 b ina file unit 40 thereby to create an index table 41. In the index table41 are saved the data received time 42 and the URL address 43 of thereceived data. After this, the URL data management unit 38 issues a datareload request (RQ=5) shown in FIG. 2 and FIG. 3 to the searching server1 via the LAN communication unit 37.

[0052] Receiving the data reload request from the satellitecommunication server 2, the reserve, search, and delivery unit 13provided in the searching server 1 prepares for receiving the latest URLdata 40 a and the data received time 42 from the satellite communicationserver 2. Hereafter, the unit 13 receives the data received time 42 andthe URL 43 set in the index 41, as well as the data 40 a and 40 bsequentially from the satellite communication server 2 thereby to updatethe searched data management table 30, as well as the table 33 and thedata 34 in the cache file 3 respectively.

[0053] After this, the reserve, search, and delivery unit 13 transmitsthe data 34 corresponding to the RURL 28 to the client terminals 6 a, 6b, 6 c, etc. via the LAN 4, the router 5 a, and the LAN 5 for eachreserve request issued from a client terminal, that is, for each IPaddress 27 a of a client terminal registered in the user table 27. Thedelivery unit 13 responses “latest data present” to the object clientterminal if a status check request (EQ=3) shown in FIG. 2 and FIG. 3 isissued from the client terminal.

[0054] In the embodiment shown in FIG. 1, the client terminals 6 a to 6c are connected to the network LAN 5. However, the above mentionedoperation of the reserved searching function is also executed if thoseclient terminals 6 a to 6 c are connected to the searching server 1 viaa public network respectively. In addition, the present invention canalso be used in any network environment if a computer program thatexecutes the above mentioned method of the present invention is recordedin a recording medium.

[0055] According to the present invention, the latest data can becollected automatically at fixed intervals of time if reserved searchrequests are registered beforehand when data that is not needed urgentlyand can be searched any time is to be searched and collected from WWWservers connected to the Internet. It is thus possible to solve theabove mentioned conventional problem that the response time to such asearch request is very slow.

[0056] Furthermore, according to the present invention, reserved searchrequests issued from a plurality of users, that is, client terminals canbe processed collectively and collected data can be receivedcollectively by a network access center existing in a specific relayarea (hub area) through a route independent of the Internet, moreconcretely, via a route that uses a communication satellite exclusively.It is thus possible to reduce the request processing time significantlywhen in a batched transfer processing.

What is claimed is:
 1. A reserved request type of searched informationdistribution server, comprising: means for issuing a search request toanother server connected to the Internet via the Internet so thatdesired data is collected from a WWW server specified by said searchrequest according to a schedule specified by a request from a clientterminal connected to said reserved request type of searched informationdistribution server via a network; and means for receiving searched datafrom said another server via a communication satellite.
 2. Aninformation distribution server, comprising: means for accessing, whenreceiving a search request from a terminal via the Internet, a WWWserver specified by said search request thereby to collect desired data;and means for transmitting collected data to said terminal via acommunication satellite.
 3. A reserved request type of searchedinformation distribution server, comprising: first controlling means forreceiving a search request from a client terminal and issuing a searchrequest to a network access center connected to the Internet so as tosearch and collect desired data from a server connected to the Internetat a fixed time according to said search request; second controllingmeans for receiving searched data from said network operation center viaanother network independent of the Internet and transmitting saidreceived data plus the data received time to said first controllingmeans; and first storing means for storing both searched data and datareceived time transmitted from said second controlling means so thatsaid searched data and said data received time are paired.
 4. A reservedrequest type of searched information distribution server according toclaim 3, wherein said first controlling means is configured to issue asearch request to a network operation center connected to the Internetso as to search and collect desired data from a server connected to theInternet at a time specified by said first type search request when asearch request issued from a client terminal is a first type searchrequest, to check if there is any data corresponding to said searchrequest from said client terminal in said first storing means when saidsearch request from said client terminal is a second type searchrequest, and to transmit data stored in said first storing means to saidrequest source client terminal if said data is present and to issue asearch request to said network access center if said data is notpresent.
 5. A reserved request type of searched information distributionserver according to claim 4, wherein said first controlling-meanscomprises second storing means for storing the address of said clientterminal and the address of an object server connected to the Internetspecified by a search request issued from a client terminal if thesearch request is of said first type; and means for transmitting theaddresses of said servers connected to the Internet, which are stored insaid second storing means, at a time specified by said search requestissued from said client terminal to said network access centercollectively.